CN110884567B

CN110884567B - Front body structure of vehicle

Info

Publication number: CN110884567B
Application number: CN201910842110.5A
Authority: CN
Inventors: 榎晃一; 阿部淳一
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2018-09-10
Filing date: 2019-09-06
Publication date: 2022-01-14
Anticipated expiration: 2039-09-06
Also published as: JP7020351B2; US11072372B2; CN110884567A; JP2020040502A; US20200079434A1

Abstract

The present application relates to a front vehicle body structure of a vehicle. The front side member (20) has a front portion (42) extending the upper joint flange portion (41) outward in the vehicle width direction at the front portion. A reinforcement plate (32) is welded to the vehicle transverse direction outer side surface of the front section (42) in an overlapping manner. The reinforcement plate (32) has a flange (52) welded so as to overlap the upper joint flange (41) of the front side member (20). The rear edge of the reinforcement plate (32) is located at the same position as the rear edge of the front portion (42), or at a more rearward position. Deformation of the front portion (42) and the upper joint flange (41) is suppressed by the reinforcing plate (32), and collapse of the closed cross-sectional structure of the front side frame (20) is suppressed.

Description

Front body structure of vehicle

Cross Reference to Related Applications

Priority of a japanese patent application No. 2018-1699072 filed 2018, 9, 10, is claimed, the entire contents of which, including the specification, claims, drawings and abstract of the specification, are incorporated herein by reference.

Technical Field

The present disclosure relates to a front body structure of a vehicle, and more particularly, to reinforcement of a front side member.

Background

The front vehicle body structure, which is a portion forward of a passenger compartment of the vehicle, includes a pair of front side frames extending in a longitudinal direction of the vehicle on the left and right sides of the portion. The front side member receives a collision load from the front side at the time of a frontal collision, and absorbs collision energy by deforming itself.

Patent document 1 below shows a front side member (12) and a gusset plate (40) disposed on the vehicle transverse direction outer side of the front side member (12). The front side member (12) has a closed cross-sectional structure in which a front side member outer section (38) located on the outer side in the vehicle width direction and a front side member inner section (39) located on the inner side are joined together. The gusset (40) transmits the collision load received by the end of the front bumper reinforcement (16) to the front side member (12) in the event of a small overlap collision or the like. The above-mentioned symbols in parentheses are those used in patent document 1 below, and are not related to those used in the description of the embodiments of the present application.

Prior art documents

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-117433

In a frontal collision, the front side frame is deflected by the collision load, and the collision energy is absorbed. If the joint between the vehicle width direction outer member and the inner member forming the closed cross-sectional structure is broken at the time of the occurrence of the deflection, the closed cross-sectional structure is broken. This may cause the strength to be insufficient, and the front side frame may not be deformed as expected at the time of a collision, and the amount of absorption of collision energy may be reduced to an expected amount.

Disclosure of Invention

The present disclosure is a technique for suppressing collapse of a closed cross-sectional structure of a front side frame at the time of a frontal collision.

The vehicle front body structure according to the present disclosure includes: a pair of front side members that are disposed on the left and right sides of a vehicle front portion, extend in the longitudinal direction of the vehicle, and are formed into a closed cross-sectional structure by joining an outer member and an inner member that is positioned on the vehicle width direction inner side of the outer member; and a reinforcement panel that is disposed so as to overlap a portion of a side surface of the front side member on the vehicle transverse direction outer side. In the front side member, joint flange portions formed by joining flanges provided on the outer member and the inner member, respectively, are formed at upper or lower edges of the vehicle width direction outer side. The front side member has a front portion at the front portion, in which the joint flange portion extends in the vehicle width direction, and a rear portion at the rear portion, in which the joint flange portion extends in the vertical direction. The reinforcement panel is disposed so as to overlap at least a part of the vehicle transverse direction outer side surface of the closed cross-section structure portion of the front portion and at least a part of the joining flange portion of the front portion, and at least a part of the rear edge of the reinforcement panel on the joining flange portion side is located at the same position as the rear edge of the front portion or is located further rearward beyond the rear edge of the front portion.

By reinforcing the joint flange portion of the front side frame and the vicinity thereof with the reinforcing plate, when the front side frame is deflected by a frontal collision, the joint flange portion is prevented from being cracked and the closed cross-sectional structure is prevented from being broken.

The front side member may have a transition portion between the front portion and the rear portion, and a direction in which the flange portion extends from the rear edge of the front portion to the front edge of the rear portion changes from the vehicle width direction to the vertical direction at the transition portion. Furthermore, at least a portion of the rear edge of the reinforcement panel that engages the flange portion side is located at the transition portion.

The deformation of the front side member is made as expected by suppressing the collapse of the closed cross-sectional structure of the front side member by the reinforcing plate.

Drawings

Fig. 1 is a plan view schematically showing a main part of a front vehicle body structure of a vehicle.

Fig. 2 is a side view schematically showing a main part of a front vehicle body structure of a vehicle.

Fig. 3 is a perspective view showing the structure of the front side frame and the components around it.

Fig. 4 is a side view showing the structure of the front side member and the components around it.

Fig. 5 is a sectional view of a front portion of the front side member.

Fig. 6 is a cross-sectional view of a transition portion of the front side member.

Fig. 7 is a sectional view of a rear portion of the front side member.

Fig. 8 is a plan view showing a state of deformation of the front side frame at the time of a frontal collision.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following description, unless otherwise specified, words indicating relative positions and directions such as front, rear, left, right, upper, lower, and lower indicate directions and positions relating to the vehicle. The front-rear direction of the vehicle is referred to as the longitudinal (longitudinal) direction, the left-right direction is referred to as the lateral (lateral) direction, and the up-down direction is referred to as the vertical (vertical) direction. Further, a side closer to a center line extending in a longitudinal direction of the vehicle in a lateral direction of the vehicle (vehicle width direction) is referred to as a vehicle width direction inner side, a direction toward the center line is referred to as a vehicle width direction inner side, a side farther from the center line is referred to as a vehicle width direction outer side, and a direction away from the center line is referred to as a vehicle width direction outer side. In the drawings, arrow FR indicates the front, arrow UP indicates the upper, arrow LH indicates the left, and arrow OUT indicates the outer in the vehicle width direction.

Fig. 1 and 2 are views schematically showing a front portion of a vehicle 10, with fig. 1 being a plan view and fig. 2 being a side view. In a vehicle such as a passenger car, a so-called engine compartment (engine compartment)16, which is a space partitioned by a dash wall 14 and in which a power plant such as an internal combustion engine is mounted, is generally provided in a front portion of a passenger compartment 12. The structure forming the engine compartment 16 is referred to as a front vehicle body structure 18. In addition, when the power unit is provided in a portion other than the front portion, such as the rear portion of the vehicle, a luggage compartment may be provided in the front vehicle body structure 18. The front vehicle-body structure 18 has a pair of front side members 20 extending in the longitudinal direction on the left and right of the front of the vehicle. Further, a pair of front side members 20 extend forward from the dash panel 14, and a bumper reinforcement 24 is bridged at their front ends via a crush box 22. The crush box 22 is crushed at the time of a front collision to absorb collision energy. A front side upper member 28 is provided to connect the front end of the front side member 20 and the front pillar 26. As shown in fig. 2, which is a side view, the front upper member 28 has an arcuate shape along the upper edge of the wheel house, and as shown in fig. 1, which is a plan view, the front upper member 28 is located on the vehicle width direction outer side than the front side frame 20. Between the front side member 20 and the front side upper member 28, a suspension tower 30 is provided.

The reinforcement panel 32 is disposed so as to overlap at least a portion of the vehicle transverse direction outer side surface of the front end portion of the front side member 20. The reinforcing plate 32 is joined to the front side member 20, thereby improving the rigidity and strength of the joined portion. The reinforcement panel 32 contributes, for example, to efficiently transmit the collision load input to the end portion of the bumper reinforcement 24 to the vehicle width direction outer side surface of the front side member 20 at the time of a small overlap collision.

Fig. 3 and 4 are views showing the left front side frame 20 and its peripheral members, with fig. 3 being a perspective view and fig. 4 being a side view. The right front side member 20 is symmetrical to the left front side member 20. Further, fig. 5 is a sectional view taken along line a-a shown in fig. 4, fig. 6 is a sectional view taken along line B-B shown in fig. 4, and fig. 7 is a sectional view taken along line C-C shown in fig. 4.

The front side member 20 is an elongated member of a closed cross-sectional structure. The cross-sectional shape can be, for example, a rectangle. As shown in fig. 5 to 7, the front side member 20 is formed by joining an outer side member 34 positioned on the vehicle width direction outer side and an inner side member 36 positioned on the inner side by welding, for example, spot welding. The outer member 34 and the inner member 36 are formed by forming a steel plate by press forming or the like. In the cross section of the front side member 20, the outer side member 34 and the inner side member 36 are welded together at the upper corners and the lower side edges of the vehicle width direction outer sides at portions corresponding to the substantial centers. An edge of the closed cross-sectional structure portion of the front side member 20, which is formed by the vehicle width direction outer side surface 20a and the upper surface 20b, is referred to as an outer upper edge 20 c.

The outer member 34 and the inner member 36 of the front side member 20 are provided with welding flanges along the outer upper edges 20c, respectively. The flange for welding of the outer member 34 is referred to as an outer upper flange 38, and the flange for welding of the inner member 36 is referred to as an inner upper flange 40. The outer upper flange 38 and the inner upper flange 40 are joined together by welding, thereby forming an upper joint flange portion 41. The upper joint flange portion 41 extends from the outer upper edge 20c of the front side member 20 in a direction away therefrom.

At the front portion of the front side member 20, an upper joint flange portion 41 extends outward in the vehicle width direction in the manner shown in fig. 5. On the other hand, an upper joint flange 41 extends upward in the vertical direction at the rear portion of the front side member 20 in the manner shown in fig. 7. A portion of the front side member 20, in which the upper joint flange portion 41 extends outward in the vehicle width direction, is referred to as a front portion 42. The portion of the front side member 20 extending upward from the upper joint flange 41 is referred to as a rear portion 44. The upper joint flange 41 extends diagonally in the vehicle width direction and in the vertical direction, i.e., in the direction perpendicular to the vehicle width direction, in a portion between the front portion 42 and the rear portion 44, as shown in fig. 6. The direction in which the upper joining flange portion 41 of this portion extends smoothly changes upward in the vehicle width direction from the rear edge of the front portion 42 to the front edge of the rear portion 44. Thus, the upper joint flange portion 41 is continuous across the entire front side member 20. The portion of the front side member 20 between the front portion 42 and the rear portion 44 is referred to as a transition portion 46.

Welding flanges are provided at portions of the outer member 34 and the inner member 36 corresponding to substantially the center of the lower surface 20d of the front side member 20 (see fig. 5 to 7). The flange of the outer member 34 disposed on the lower surface 20d is referred to as an outer lower flange 48, and the flange of the inner member 36 is referred to as an inner lower flange 50. The front side member 20 is formed into a substantially rectangular closed cross-sectional structure by welding the outer upper flange 38 and the inner upper flange 40, and welding the outer lower flange 48 and the inner lower flange 50.

In the front portion 42, the upper joint flange portion 41 is disposed in a plane (hereinafter, referred to as a horizontal plane) defined by the longitudinal direction and the lateral direction, and therefore contributes to rigidity and strength with respect to bending in the horizontal plane of the front side member 20. In the rear portion 44, the upper joint flange portion 41 is disposed in parallel with a steel plate forming the suspension tower 30 and is welded to the steel plate.

The reinforcement plate 32 is disposed at the front portion 42 so as to overlap with the vehicle transverse direction outer side surface 20a of the front side member 20, and is further welded to the side surface 20 a. The reinforcement plate 32 has a reinforcement plate upper flange 52 that overlaps the outer upper flange 38 and the inner upper flange 40. These

upper flanges

38, 40, 52 may be welded together simultaneously in a three-piece overlapping manner. The reinforcing plate 32 has a reinforcing plate lower flange 54 that overlaps the outer lower flange 48 and the inner lower flange 50. These

lower flanges

48, 50, 54 may be welded together simultaneously in a three-piece overlapping manner.

The reinforcement panel 32 extends from the front end of the front side member 20 at least as far as the rear edge of the front portion 42. The reinforcement panel 32 may extend further rearward beyond the rear edge of the front portion 42 so that the rear edge 32a of the reinforcement panel 32 may be located within the transition portion 46. The reinforcement panel upper flange 52 and the reinforcement panel lower flange 54 also extend at least as far as the rear edge of the forward portion 42 and may further extend toward the transition portion 46.

The reinforcing plate 32 may be welded to the side surface 20a of the front side member, as well as to the flange portion. Ridge-like protrusions 56 extending in the longitudinal direction may be formed on the reinforcing plate 32. Although two ridges 56 are provided in the illustrated example, one or more than three ridges may be provided.

Fig. 8 is a plan view schematically showing a state in which the left front side frame 20 is deformed as expected due to a frontal collision. When a collision load F is applied to the front side member 20 from the front, an inward bend that bends inward in the vehicle width direction is generated in the front side member 20 at or near the transition portion 46. Further, an outer bend that bends outward in the vehicle width direction is generated at substantially the center of the rear portion 44.

When the joint portion of the outer member 34 and the inner member 36 is broken and the closed cross-sectional structure cannot be maintained, the bending does not occur at the assumed position shown in fig. 8, but occurs at the assumed portion. In the front portion 42, since the plate materials of the outer upper flange 38 and the inner upper flange 40 are arranged in the horizontal plane, when a bending moment in the horizontal plane acts, these

flanges

38, 40 are deformed so as to be separated from each other. As a result, the joint portion may peel off, and the flange portion may crack, thereby collapsing the closed cross-sectional structure. In particular, in the case of joining by spot welding, stress concentrates in the vicinity of the welding point, and cracks occur around the welding point of the member, and the flange portion is cracked starting from this.

A reinforcement plate 32 is disposed at a front portion 42 of the front side member 20, the flange portion of which is easily cracked, in order to suppress deformation. The reinforcing plate 32 suppresses deformation of the front portion 42. In particular, the reinforcement plate upper flange 52 reinforces the outer upper flange 38 and the inner upper flange 40, thereby suppressing deformation thereof. This suppresses the collapse of the closed cross-sectional structure of the front portion 42, and the front side member 20 is deflected as expected.

In order to suppress the deformation of the front portion 42, it is effective to suppress the deformation of the outer upper flange 38 and the inner upper flange 40 and their peripheries, and the reinforcing plate 32 extends to the rear edge of the front portion 42 on the side where the outer upper edges 20c of these

flanges

38, 40 are provided, or extends to the transition portion 46 beyond the rear edge. The reinforcement panel 32 may extend to a lower or central portion, which is the opposite side of the outer upper edge 20c, without reaching the rear edge of the front portion 42, as long as the closed cross-sectional structure can be maintained. Further, the front end of the gusset upper flange 52 may not reach the front end of the front portion 42.

In the above-described embodiment, the

welding flanges

38 and 40 are provided on the outer upper edge 20c of the front portion 42 of the front side member 20, but a welding flange may be provided on the outer lower edge instead of or in addition to these flanges. The reinforcing plate extends to the rear edge or transition 46 of the front portion 42 on the side where the welding flange is provided.

Description of the symbols

10 … vehicle; 12 … passenger compartment; 14 … front wall of the compartment; 16 … engine compartment; 18 … front vehicle body structure; 20 … front longitudinal beams; 20c … outer upper edge; 22 … crash box; 24 … bumper reinforcement; 26 … front pillar; 28 … front upper member; 30 … suspension tower; 32 … reinforcing panels; 32a … (of the stiffener plate) rear edge; 34 … an outer member; 36 … inner part; 38 … outer upper flange; 40 … inner upper flange; 41 … upper engagement flange portion; 42 … front portion; 44 … rear portion; 46 … transition portion; 48 … outer lower flange; 50 … inner lower flange; 52 … stiffening the panel upper flange; 54 … stiffening the panel lower flange; 56 ….

Claims

1. A front vehicle body structure of a vehicle, comprising:

a front side member that is disposed on the left and right of a front portion of a vehicle, extends in a longitudinal direction of the vehicle, and is formed into a closed cross-sectional structure by joining an outer member and an inner member positioned on a vehicle width direction inner side of the outer member, wherein a joint flange portion is formed at an upper edge or a lower edge on a vehicle width direction outer side by joining a flange provided on the outer member and a flange provided on the inner member, and the front side member has a front portion at a front portion where the joint flange portion extends so as to be apart from the closed cross-sectional structure toward the vehicle width direction outer side, and a rear portion at a rear portion where the joint flange portion extends in a vertical direction;

and a reinforcement panel that is disposed so as to overlap at least a part of a vehicle width direction outer side surface of the closed cross-section structure portion of the front portion and at least a part of the joining flange portion of the front portion, and that has at least a part on the joining flange portion side of a rear edge located at the same position as a rear edge of the front portion or located further rearward beyond the rear edge of the front portion.

2. A front vehicle-body structure of a vehicle according to claim 1,

the front side member has a transition portion between the front portion and the rear portion, at which a direction in which the joint flange portion extends from a rear edge of the front portion to a front edge of the rear portion changes from a vehicle width direction to a vertical direction,

at least a portion of the rear edge of the reinforcement panel on the side of the engagement flange is located at the transition portion.